Fig 45. — Hydra. A veitical section of entire animal; B, portion of transverse 

 section, highly magnified.; C, two large ectoderm cells: D, endoderm ctll of 

 // viridis ; E, large nematocyst; F, small nematocyst; G, sperm; a, ingested 

 diatom; 3d. 1 , bd. % , buds; chr, chromatophores; cnbi, cnidoblast; cnc, cnidocil; 

 ect, ectoderm; e?id, endoderm; ent. cav, enteric cavity; eiit cav x , its prolonga- 

 tion inlo the tentacles; J7, flapellum; hyfi, hypostome or manubrium; iut c, in- 

 terstitial cells; m fir, muscle processes; ?nth, mouth; ntsgl, mesoglcea; net, 

 large, and ntc 1 , small nematocysts; ;/w, nucleus; ov, ovum; ovy, ovary; fisd, 

 pseudopods; sfiy, spermary; vac, vacuole, 



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